[mlir][dxsa] Add dcl_hs_max_tessfactor instruction

mlir/include/mlir/Dialect/DXSA/IR/DXSAOps.td

@@ -771,4 +771,23 @@ def DXSA_DclOutputSiv : DXSA_Op<"dcl_output_siv"> {
   let assemblyFormat = "$operand `,` $name attr-dict";
 }
 
+def DXSA_DclHsMaxTessFactor : DXSA_Op<"dcl_hs_max_tessfactor"> {
+  let summary = "declares the MaxTessFactor for the patch";
+  let description = [{
+    The `dxsa.dcl_hs_max_tessfactor` operation declares the MaxTessFactor
+    for the patch.
+
+    The `$max_tessfactor` is a float32 value in the range [1.0, 64.0].
+
+    Example:
+
+    ```mlir
+    dxsa.dcl_hs_max_tessfactor 4.200000e+01
+    ```
+  }];
+  let arguments = (ins F32Attr:$max_tessfactor);
+  let assemblyFormat = "$max_tessfactor attr-dict";
+  let hasVerifier = 1;
+}
+
 #endif // DXSA_OPS

mlir/lib/Dialect/DXSA/IR/DXSA.cpp

@@ -54,6 +54,15 @@ LogicalResult DclIndexRange::verify() {
   return success();
 }
 
+LogicalResult DclHsMaxTessFactor::verify() {
+  auto value = getMaxTessfactorAttr().getValue();
+  if (!value.isFinite() || value < llvm::APFloat(1.0f) ||
+      value > llvm::APFloat(64.0f))
+    return emitOpError("MaxTessFactor must be in [1.0, 64.0], got ")
+           << value.convertToFloat();
+  return success();
+}
+
 //===----------------------------------------------------------------------===//
 // TableGen'd attribute method definitions
 //===----------------------------------------------------------------------===//

mlir/lib/Target/DXSA/BinaryParser.cpp

@@ -12,6 +12,7 @@
 #include "mlir/IR/Location.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/bit.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/DebugLog.h"
 #include "llvm/Support/Endian.h"
@@ -653,6 +654,11 @@ class DXBuilder {
     return dxsa::DclOutputSiv::create(builder, loc, operand, nameAttr);
   }
 
+  Instruction buildDclHsMaxTessFactor(float maxTessFactor, Location loc) {
+    return dxsa::DclHsMaxTessFactor::create(
+        builder, loc, builder.getF32FloatAttr(maxTessFactor));
+  }
+
 private:
   MLIRContext *context;
   ModuleOp module;
@@ -1216,6 +1222,13 @@ class Parser {
     return builder.buildDclOutputSiv(*operand, *name, loc);
   }
 
+  FailureOr<Instruction> parseDclHsMaxTessFactor(Location loc) {
+    auto token = parseToken();
+    FAILURE_IF_FAILED(token);
+    auto maxTessFactor = llvm::bit_cast<float>(*token);
+    return builder.buildDclHsMaxTessFactor(maxTessFactor, loc);
+  }
+
   OptionalParseResult parseDclInstruction(uint32_t opcodeToken, Location loc,
                                           Instruction &out) {
     FailureOr<Instruction> result;
@@ -1271,6 +1284,9 @@ class Parser {
     case D3D10_SB_OPCODE_DCL_OUTPUT_SIV:
       result = parseDclOutputSiv(loc);
       break;
+    case D3D11_SB_OPCODE_DCL_HS_MAX_TESSFACTOR:
+      result = parseDclHsMaxTessFactor(loc);
+      break;
     default:
       return std::nullopt;
     }

mlir/test/Target/DXSA/dcl_hs_max_tessfactor.mlir

@@ -0,0 +1,5 @@
+// RUN: mlir-translate --import-dxsa-bin %S/inputs/dcl_hs_max_tessfactor.bin | FileCheck %s
+
+// CHECK:      module {
+// CHECK-NEXT:   dxsa.dcl_hs_max_tessfactor 4.200000e+01
+// CHECK-NEXT: }

mlir/test/Target/DXSA/dcl_hs_max_tessfactor_invalid.mlir

@@ -0,0 +1,29 @@
+// RUN: mlir-opt %s -split-input-file -verify-diagnostics
+
+// expected-error@+1 {{'dxsa.dcl_hs_max_tessfactor' op MaxTessFactor must be in [1.0, 64.0], got 5.000000e-01}}
+dxsa.dcl_hs_max_tessfactor 0.5
+
+// -----
+
+// expected-error@+1 {{'dxsa.dcl_hs_max_tessfactor' op MaxTessFactor must be in [1.0, 64.0], got -1.000000e+00}}
+dxsa.dcl_hs_max_tessfactor -1.000000e+00
+
+// -----
+
+// expected-error@+1 {{'dxsa.dcl_hs_max_tessfactor' op MaxTessFactor must be in [1.0, 64.0], got 6.500000e+01}}
+dxsa.dcl_hs_max_tessfactor 6.500000e+01
+
+// -----
+
+// expected-error@+1 {{'dxsa.dcl_hs_max_tessfactor' op MaxTessFactor must be in [1.0, 64.0], got nan}}
+dxsa.dcl_hs_max_tessfactor 0x7FC00000
+
+// -----
+
+// expected-error@+1 {{'dxsa.dcl_hs_max_tessfactor' op MaxTessFactor must be in [1.0, 64.0], got INF}}
+dxsa.dcl_hs_max_tessfactor 0x7F800000
+
+// -----
+
+// expected-error@+1 {{'dxsa.dcl_hs_max_tessfactor' op MaxTessFactor must be in [1.0, 64.0], got -INF}}
+dxsa.dcl_hs_max_tessfactor 0xFF800000